Cleaning and separating tableware

ABSTRACT

A VIBRATORY BOWL FEEDER IS EMPOLYED TO WASH TABLEWARE AND SEPARATE INDIVIDUAL PIECES FOR DELIVERY, FOR EXAMPLE, TO A TABLEWARE SORTER.

M r 1971 o. L. NYSTUEN CLEANING AND SEPARATING TABLEWARE Filed Oct. 11 1968 DAVH) L. NYSTUEN HY 7 1 K MMM United States Patent Ofice Patented Mar. 2, 1971 ABSTRACT OF THE DISCLOSURE A vibratory bowl feeder is employed to wash tableware and separate individual pieces for delivery, for example, to a tableware sorter.

This invention relates to cleaning tableware, such as knives, forks and spoons and, in particular, provides an apparatus and process not only for cleaning but for separating individual pieces of tableware.

A primary object of this invention is to provide more effective cleaning of masses of tableware, such as knives, forks and spoons, particularly mixed masses of such tableware.

It is also an important object of this invention to provide for separating the individual pieces of tableware as they are washed so that they may be delivered as individual pieces, for example, to a sorting device.

In accordance with this invention, it has been found that these and other objects are obtained utilizing a washing tank constructed as a vibratory bowl feeder. As is Well known, vibratory bowl feeders generally include a bowl,

having an open top with a helical flight extending inside the sidewall of the bowl from the bottom to the top of the bowl. The bowl is normally mounted on springs, such as leaf-springs, in a manner such that the bowl can be caused to vibrate on the springs through a short vertical distance, while simultaneously twisting along a helical path having the same direction of lay with respect to the axis of twisting as that of the helical flight along the inside of the sidewall of the bowl.

As is also well known, such feeders are commonly used to separate individual articles from a mass of identical articles. The separated articles ride slowly up the flight to the top of the bowl and a point of utilization. Surprisingly, however, when a mass of tableware of various shapes and weight is positioned in the bottom of such a vibratory bowl feeder immersed in a detergent solution, the same action occurs even though one would expect that the separate weights and shapes of table pieces would ride the flight at different rates of speeds and thus knock one another off. Surprisingly, moreover, as the individual table pieces in the mass are inter-tangled, one would not expect them to become separated. Furthermore, the cleaning action that results is substantially superior to that obtained with using ultrasonic methods and vibrating baskets. I

For a more complete understanding of the application of this invention, reference is made to the appended drawings, in which:

FIG. 1 is'a partially sectioned elevation of a washing tank for cleaning tableware in accordance with this invention; and

FIG. 2 is a plan view of the tank shown in FIG. 1.

Referring to the drawings, the reference numeral indicates a washing tank which is of generally cylindrical construction being open at its top, and having a cylindrical sidewall 11 and flat closed bottom 12. On the inner side of sidewall 11 a flight 13 of helical shape winds about sidewall 11 beginning at the bottom of tank 10 leading after several convolutions to the top of tank 10 where it leads off through a tangential, horizontal platform 14.

Flight 13 has a transverse dimension wide enough to support the widest piece of tableware to be cleaned" and separated, yet narrow enough such that it will not support more than two pieces of tableware abreast.

Tank 10 is mounted at its bottom 12 on four leafsprings '15 which are secured at their upper ends to the underside of bottom 12 at intervals and which at their lower ends are mounted at 90 intervals about a baseplate 16. Each of leaf-springs 15 is mounted on the same angle from the vertical with respect to the vertical axis of tank 10, such that tank 10 can twist about its vertical axis through a path which is helical with the same direction of lay with respect to such axis as has flight 13. It will be noted, moreover that the pitch of twisting path of tank 10 when vibrated on leaf-springs 15 is steeper than the pitch of helical flight 13.

Centrally on baseplate 16 there is mounted a solenoid 17 which has a vertical armature 18 secured at its upper end to the center of the underside of bottom 12. Thus, energization of solenoid 17 will produce a helical oscillation of tank 10.

Except that tank 10 is constructed with a high sidewall to permit a number of convolutions of flight 13, tank 10 does not, as far as described above, mechanically differ from the conventional vibratory bowl feeder, either in mounting or manner of vibration. Tank 10 is, however, provided with two flexible horizontal over-flows 19 and 20 connecting tank 10 to wash solution reservoir 21.

Tank 10 is further provided with a detergent inlet pipe 23 which leads downwardly through the upper end of tank 10 to a position where it is provided with a sparger 24v located above inlet 20 with sparger 24 directed to discharge incoming detergent solution onto flight 13.

Tank 10 is also provided with a rinse water inlet 25 for delivering fresh water which also enters and leads downwardly into tank 10 to a position where it terminates in a sparger 26, which is directed to deliver fresh water through inlet 25 onto flight 13 at a location above sparger 24. Finally tank 10 is also provided with a hot air inlet 27 which enters tank 10 through its open top and terminates in tank 10 in a discharge nozzle 28 which is directed on flight 13 at a location higher than sparger 26.

Reservoir 21 contains a heating element 29 and a drainpipe 30 which extends upwardly into reservoir 21 to a screened intake 31. Drainpipe 30 leads to the suction side of a discharge pump 32 which is connected on its positive side to line 23.

Reservoir 21 also contains a liquid level control pipe 33 leading to drain valve 34. The reservoir 21 can also be equipped with a conductivity sensing element for determining detergent concentration and with means for continuously supplying detergent responsive to the sensing element.

In operation, tank 10 is set into vibration by energizing solenoid 17 with ordinary 601/ power, thus vibrating tank 10 at 3600 cycles per minute. Hot water at a suitable temperature, such as F., containing a commercial detergent is introduced through inlet 23 until tank 10 fills to the point where the detergent solution passes through over-flow 20. Hot rinse water is similarly introduced through inlet 25 and hot air is introduced through inlet 27.

Tableware, including mixtures of various sizes of knives, forks and spoons, is then thrown into the center of tank 10 where it falls to the bottom in a jumbled, tangled mass immersed in the detergent solution. The vibratory action promptly not only rinses the soiled food matter from the tableware but causes the tableware to separate and piece by piece to ride individually up flight 13. It has been found that required washing time at a vibration rate of 3600 cycles per minute is approximately three minutes. Consequently, the location of inlet 20 should be designed such that the immersion time of the tableware in the detergent solution, including the time required to ride up flight 13 below the level of detergent solution, determined by inlet 20 totals three minutes. As the various individual pieces travel up flight 13 further, they are first cleaned with clean detergent solution from sparger 34 and then rinsed with fresh rinse water from sparger 36 and are thereafter dried in the hot air stream from nozzle 28. The cleaned, dried and separated table pieces as they reach the top of flight 13 are delivered onto platform 14 which desirably is directed to introduce the pieces into a sorting apparatus for sorting as to size and type of table piece. It will be appreciated that the present invention thus readily lends itself to a continuous cleaning operation as well as the batch-type operation heretofore always required in tableware cleaning.

Little significance has been attached to materials of construction, but it has been found that better operations are achieved using a tank which has a surface of synthetic resinous material rather than a metallic surface. Consequently, a plastic coated tank is preferred.

What is claimed is:

1. A process for cleaning and separating a mixture of soiled tableware comprising at least two of knives, forks and spoons, which includes positioning said mixture of tableware on the flat unobstructed bottom of a tank having a helical flight extending on the innerside of the sidewall of the tank from the bottom to the top of the tank, maintaining a detergent solution in said tank, and vibrating said tank through a short helical path having the same direction of lay as said flight, whereby said tableware is cleaned by vibratory action in said detergent solution and is separated into individual pieces which ride up said flight to the top of said tank.

2. An apparatus for cleaning and separating a mixture of soiled tableware comprising at least two of knives, forks and spoons, which includes a tank having a flat unobstructed bottom and having a helical flight extending on the innerside of the sidewall of the tank from the bottom to the top of the tank, the transverse dimension of the helical flight being sufficient to support the widest piece of tableware to be cleaned and separated but insufiicient to support more than two pieces of tableware abreast, means for maintaining a detergent solution in said tank, and means for vibrating said tank through a short helical path having the same direction of lay as said flight, whereby tableware positioned on the bottom of said tank is cleaned by vibrating action in said detergent solution and is separated into individual pieces which ride up said flight to the top of said tank.

3. An apparatus according to claim 2 which further includes means for rinsing said tableware including means for directing rinse water on said individual pieces riding up said flight at a location above said detergent solution.

4. An apparatus according to claim 2 which further includes means for drying said tableware including means for directing air on said individual pieces riding up said flight at a location above said detergent solution.

References Cited UNITED STATES PATENTS 2,662,851 12/1953 Jones et al. 1314-132X 2,746,468 5/ 1956 Desmond et a1 134-132X 2,760,503 8/1956 Carrier 134-132 2,760,504 8/1956 Spurlin 134--132 2,980,121 4/1961 Schuricht et al 134-132X 3,216,431 11/1965 White 13483X JOSEPH SCOVRONEK, Primary Examiner D. G. MILLMAN, Assistant Examiner U.S. Cl. X.R. 

